Probably just another question you have had a hundred times, why has the OnePlus 7pro not been included as stadia ready? This was voted handset of the year last year and was the fastest phone?
Especially at this time with Corona etc why doesn't Google open up the app ? To all phones of a certain spec ?
I cannot answer your question why the One Plus Pro 7 is not supported but maybe this workaround from Reddit will help you. Otherwise if you a brave enough you can follow the XDA Developers guide.
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